Adding Reference Images to Blender

See http://blender.stackexchange.com/questions/118/how-do-i-set-a-background-image-while-i-am-editing for source!

You can create an Empty->Image in the scene, and then in properties for the Empty, add your image to it. Tick the transparency to about 0.5, and enable X-ray in the Object Properties tab, and it should be always visible!

I usually like to put one for front view, and one for side view, showing them only if the camera is facing directly forward or on the side.